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Environmental Monitoring


October 2012 Issue

Antarctic Ice Core Shows 15,000-Year Record of Climate Changes
A 15,000-year climate history reconstructed from an ice core collected from James Ross Island in the Antarctic Peninsula was published in Nature in August. The study found the rapid warming of the region over the last 100 years has been unusual and occurred atop a slower, natural climate warming that began around 600 years ago. By the time the recent warming began, the Antarctic Peninsula ice shelves were already poised for the dramatic breakups observed since the 1990s. The peninsula is one of the world’s fastest-warming places. Average temperatures rose nearly 2° C in the past 50 years.

“One of the key questions that scientists are attempting to answer is how much of the Earth’s recently observed warming is due to natural climate variation and how much can be attributed to human activity since the industrial revolution,” lead author Dr. Robert Mulvaney of British Antarctic Survey said. “The only way we can do this is by looking back through time when the Earth experienced ice ages and warm periods, and ice cores are a very good method for doing this.”

Within the 364-meter-long core are layers of snow that fell every year for the last 50,000 years. Chemical analysis was used to recreate a temperature record over this period, which showed that the Antarctic Peninsula warmed by about 6° C as it emerged from the last ice age.

About 11,000 years ago, the temperature was about 1.3° C warmer than today’s average. The Antarctic Peninsula ice sheet was shrinking at the time, and some of the surrounding ice shelves retreated. The local climate then cooled until about 600 years ago, during which the ice shelves on the northern Antarctic Peninsula expanded.

Afterward, the local temperature started to warm again, followed by a more rapid warming in the last 50 to 100 years that coincides with present-day disintegration of ice shelves and glacier retreat.

EmissionManager Systematizes Environmental Data and Reports
In cooperation with Hamburg Süd Group (Hamburg, Germany), Germanischer Lloyd (Hamburg) has developed the GL EmissionManager system, launched in September, to systematically capture environmentally relevant ship operation data and generate coordinated reports.

Operational and voyage-related data, such as noon position, departure, arrival and stoppage are recorded and analyzed. Environmental information is extracted, including fuel consumption; CO2, sulfur oxide and nitrogen oxide emissions; garbage; sludge; ballast water and chemicals.

The system comprises emission recorder software and the Green Server. The recorder is installed on the computer of the participating vessel, creating voyage and operation reports from standard forms, which are transferred to the Green Server, which tracks all reports.

E-mails regarding standard events such as port departure are automatically sent from the vessel to the Green Server. The system can be used for comprehensive fleet analysis, regulatory or classification purposes, or environmental shipping databases.

USCG Approves NSF International For Evaluating Ballast Water
NSF International (Ann Arbor, Michigan) became in September the first independent laboratory accepted by the U.S. Coast Guard (USCG) to evaluate and test technologies designed to treat ballast water on ships to prevent the spread of non-native aquatic species in lakes, rivers and coastal waters.

Ballast water management system manufacturers will apply to NSF International and the USCG for testing, review and evaluations. Land-based testing will determine if a ballast water management system is effective to meet the ballast water discharge standard requirements of 33 CFR Part 151, Subparts C and D.

NSF is leading a partnership with Retlif Testing Laboratories (Ronkonkoma, New York), the Great Ships Initiative (GSI) and the Maritime Environmental Resource Center (MERC) to test and evaluate systems. NSF will coordinate testing among Retlif, GSI and MERC. NSF will coordinate preparation of test plans, technical and quality assurance of test data, evaluation of system material design and construction, and the operation, maintenance and safety manual. NSF will submit the test and evaluation results to the USCG.

Arctic Sea Ice at Record Low For Month of August Since 1979
In August, Arctic sea ice extent tracked below 2007 levels for a new record low for the month of 4.72 million square kilometers since satellite observations began in 1979, the National Snow and Ice Data Center said.

Extent was unusually low for all Arctic sectors, except the East Greenland Sea. Ice loss rate for August 2012 was 91,700 square kilometers per day, the fastest for the month since 1979.

August air temperatures approximately 3,000 feet above the surface remained slightly above average at 1 to 3° C over the much of the Pacific and central sectors of the Arctic Ocean, with slightly higher temperatures in the Beaufort Sea around 4° C. On the Atlantic side, the Kara and Barents seas continued to have air temperatures around 1 to 4° C below average.

Between mid-March and the third week of August, the total multiyear ice in the Arctic Ocean declined by 33 percent, and ice older than five years declined by 51 percent.

Ice age is an important indicator of ice cover health. Multiyear ice tends to be thicker and less prone to summer melt.

In recent summers, Arctic Ocean sea surface temperatures have been anomalously high, in part linked to loss of the reflective ice cover that allows darker open-water areas to readily absorb solar radiation and warm the mixed layer of the ocean.

Multiyear ice transported into the Beaufort and Chukchi seas tends to melt out in summer before being transported back to the central Arctic Ocean through the Beaufort Gyre circulation. The tongue of multiyear ice along Alaska’s coast mostly melted out by the end of August, with a small remnant left in the Chukchi.

The ice on the Arctic’s Pacific side melted back to the edge of the multiyear ice cover, which should help slow ice loss. In the Laptev Sea, a large amount of first-year ice remains.

In September, open-water areas have developed within the Laptev’s first-year ice, fostering further melt.


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